1. Field of the Invention
This application relates to thermocylers. More specifically, this application relates to systems and methods for detecting amplification of molecules using the polymerase chain reaction and other reactions.
2. Description of the Related Art
The advent of Polymerase Chain Reaction (PCR) in 1983 has revolutionized molecular biology through vastly extending the capability to identify, manipulate, and reproduce genetic materials such as DNA. Now, PCR is routinely practiced in medical and biological research laboratories for a variety of tasks, such as the detection of hereditary diseases, the identification of genetic fingerprints, the diagnosis of infectious diseases, the cloning of genes, paternity testing, and DNA computing. The method has been automated through the use of thermal stable DNA polymerases and machines capable of heating and cooling genetic samples rapidly, commonly known as thermal cyclers.
The optical measurements useful for interrogating these reactions can involve the measurement of fluorescence. To measure fluorescence, excitation light is directed at the samples in the sample vessels, and light emitted from the fluorophores in the samples is detected. It is often desirable that the transfer of light from the light source to the wells be carried out effectively and efficiently. Optical systems for directing light to sample plates is known, for example, as described in U.S. Pat. Nos. 6,942,837, 7,369,227, 6,852,986, and 7,410,793. While optical systems for directing light to sample vessels in plates and detecting light from the sample vessels have been developed in the art, there remains a need for optical systems which can do so more effectively and efficiently.